The goal of the study was to construct two valid and reliable measures for comprehension ability of English and Persian humor by advanced EFL learners in terms of Grice’s non-observed conversational maxims. To achieve the objectives of the study, a mixed-methods design was utilized in three different phases: the validation phase, the main phase, and the qualitative phase of the study. The study utilized three instruments: a Preliminary English Test (PET), an English Humor Comprehension Test (EHCT), and a Persian Humor Comprehension Test (PHCT). To examine the validity of the designed tests, Confirmatory Factor Analysis (CFA) was used. The results showed that from among the four conversational maxims, Quantity with the highest mean score (0.75) was the easiest maxim while Quality with the lowest mean score (0.41) was the most difficult maxim for the participants. Results of the descriptive statistics of the four maxims in Persian Humor Comprehension Test also indicated that among four Grice’s non-observed conversational maxims, Manner (.64) has the highest mean score which is the easiest maxim and relevance (.46) has the lowest mean score which is the most difficult maxim.